When is a crack more than a crack?

Gloomendoom

FreeBear wrote: »

If it was built before your parents were born, it is well old.

My house was built in the 1920s, and I regard it as old

By those standards, my house should be a scheduled ancient monument. Some people I know have cars older than that.

Dua_Alem

A civil engineer or specialist should come & evaluate, but if cracks are not in columns or beams generally it does not matter unless it affect the view.

SG27

FreeBear wrote: »

Yes, you can paint over lime plaster, but... To maintain breathability (vapour permeability), you should be using the correct paint - Nothing B&Q or any of the other DIY outlets are suitable. Unfortunately, most of the suitable paints are comparatively more expensive in the short term*

A couple of links for you -

• http://www.auro.co.uk/auro-paint
• http://earthbornpaints.co.uk/faqs/what-is-claypaint-and-why-is-it-so-special/
• https://www.mikewye.co.uk/product-category/paints-oils-waxes/internal-paints/

Whilst suitable paints may be expensive, over time, they will not give rise to damage to the fabric of the building which would cost even more to fix. Using a modern acrylic emulsion effectively seals the plaster and stops it breathing - Putting lining paper on first and then painting with emulsion still seals the surface, but is fairly easy to remove at a later date without major expense.

Another aspect of lime plaster which is often overlooked - Due to the materials used, lime plaster doesn't suffer from mold problems to the same extent as modern gypsum plasters (it is due to the pH of the lime). A selling point for asthma sufferers.

"Proper" paints need not be expensive if you are interested in mixing your own from scratch. A simple paint can be made from casein, lime, and raw pigments. Casein can be made in the kitchen by mixing some vinegar into warm milk and then washing the curds. Raw pigments are readily available from ebay or any decent artist shop (Cornellisen is one). Small quantities of lime might be a problem, but if you have your walls replastered in lime, ask the plasterer for a small bucket of putty.... Or if you get stuck, send me a PM.


Lots to think about when owning an older property :think:

I'd recommend Mike Wye, used them a couple of times for limewash and lime putty. No dearer than a tub of dulux from what I remember.